首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3543267篇
  免费   259320篇
  国内免费   17076篇
耳鼻咽喉   47366篇
儿科学   114529篇
妇产科学   97587篇
基础医学   494164篇
口腔科学   96554篇
临床医学   329531篇
内科学   690799篇
皮肤病学   82553篇
神经病学   288147篇
特种医学   134566篇
外国民族医学   1181篇
外科学   523444篇
综合类   92309篇
现状与发展   31篇
一般理论   1337篇
预防医学   274505篇
眼科学   81007篇
药学   259920篇
  123篇
中国医学   13156篇
肿瘤学   196854篇
  2021年   31968篇
  2019年   31215篇
  2018年   42259篇
  2017年   32951篇
  2016年   37070篇
  2015年   43064篇
  2014年   59266篇
  2013年   85461篇
  2012年   114741篇
  2011年   122094篇
  2010年   73286篇
  2009年   68974篇
  2008年   110989篇
  2007年   117437篇
  2006年   119320篇
  2005年   115089篇
  2004年   108643篇
  2003年   104705篇
  2002年   100659篇
  2001年   167494篇
  2000年   171744篇
  1999年   145119篇
  1998年   43217篇
  1997年   38663篇
  1996年   38164篇
  1995年   36834篇
  1994年   33583篇
  1993年   31081篇
  1992年   110835篇
  1991年   106361篇
  1990年   102973篇
  1989年   99095篇
  1988年   90899篇
  1987年   89022篇
  1986年   83294篇
  1985年   79679篇
  1984年   59677篇
  1983年   50574篇
  1982年   30248篇
  1979年   52674篇
  1978年   37270篇
  1977年   31399篇
  1976年   29259篇
  1975年   30847篇
  1974年   36740篇
  1973年   35105篇
  1972年   32995篇
  1971年   30512篇
  1970年   28355篇
  1969年   26996篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.  相似文献   
54.
55.
56.
57.
58.
AimsWe previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy.MethodsThe db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14.ResultsWe found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14.ConclusionOur results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery.  相似文献   
59.
60.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号